Mining machine



April 16, 1935.

c. A. PRATT MINING MACHINE Original Filed Feb. 25, 1932 3 Sheets-Sheet 1 April 16, 1935. c. A. PRATT MINING MACHINE 3 Sheets-Sheet 2 Original Filed Feb. 25, 1932 April 16, 1935.

C. A. PRATT MINING MACHINE Originai F'iIed Feb. 25. 1932 3 Sheets-Sheet 3 a L s\ \w 5 while undercutting the coal.

Patented Apr. 16, 1935 UNITED STATES 1,99 MINING PATENT OFFICE MACHINE Application February 25, 1932, Serial No. 595,054

- Renewed December 1, 1933 7 Claims.

This invention relates to improvements in mining machines and more particularly to improvements in a kerf cutting coal mining machine slidable on its own bottom on the mine bottom This invention has among other objects to provide a new and improved mining machine of the class described, the parts of which are so arranged as to afford the construction of a low, compact, and simplified machine capable of operating in thin seams of coal where roof supports are spaced close to the coal face. Another object of my invention is to arrange the parts in such a manner that a more efficient motor may be used than formerly has been used on mining machines of the class described due, principally, to the i act that the motor shafts of these prior machines have been rotatable about an axis extending longitudinally of the machine. With such an arrangement it has not been found practical to provide the motor with the usual field coil for each pole. This necessarily restricts the efficiency of the machine and in order to keep the machine to a height which will operate in low coal necessitates the use of a motor of larger longitudinal and transverse dimensions than is desirable. Another object of my invention is to provide a means whereby the motor may be readily accessible, and whereby the armature of said motor may be removed with no vertical movement thereof and very little'rearward movement thereof, the motor shell being so arranged that the armature and all of the motor parts may be accessible from one side of the motor instead of from the rearward end thereof.

My invention may be more clearly understood with reference to the accompanying drawings wherein:

Figure 1 is a top plan view of a machine constructed in accordance with my invention mounted on a truck, with parts broken away and in section to more clearly show the details thereof;

Figure 2 is a side elevation of the device shown 0 in Figure 1;

Figure 3 is a sectional view taken substantially on line 33 of Figure 1;

Figure 4 is a sectional view taken substantially on line 4 -4 of Figure'3;

Figure 5 is a sectional view taken substantially on line 55 of Figure 1;

Figure 6 is a sectional view taken substantially on line 6-6 of Figure 1; and V Figure '7 is a sectional View taken substantially on line 1-1 of Figure 1.

Like numerals refer to like parts throughout the various figures.

Referring now in particular to the details shown in the drawings, the embodiment of my invention illustrated comprises a vertically disposed motor Ifl slidable on one of its ends on the mine bottom, anda main frame II which forms a support and housing for cutting and feeding mechanism extending forwardly of said motor.

A cutter bar 52 projects forwardly from the main frame H and is secured to a projection l3 extending forwardly therefrom in a suitable manner not herein shown or described since it is no portion of my invention. The cutter bar i2 is provided with a cutter chain I4 movable thereabout in a usual manner and driven from a cutter chain sprocket i5 freely mounted on the lower end of a vertical shaft I 6. The cutter chain sprocket l5 and vertical shaft [6 are driven from motor I!) in a suitable manner which will hereinafter be more fully described.

Means are provided for moving the mining machine about the mine from working place to working place which may be of any suitable construction, but which means is herein preferably shown as being a track mounted truck ll. The truck I! is driven from the mining machine motor is} in a manner which will hereinafter be more fully described for transporting the mining machine about the mine, and is provided with a pivoted forward end so the mining machine may readily be removed therefrom or loaded thereon in a usual manner well known to those skilled in the art.

The main frame H is attached to a casing I8 for the motor ID by means of nuts and bolts indicated at 9 and forms a means for supporting the feeding and cutting mechanism and the drive means therefor. The main frame H is so arranged that a passageway is provided for discharging the cuttings from the machine, which passageway is closed to the advance and rearward sides thereof and conforms substantially to the path of the cutter chain M for discharging the cuttings to the retreating side of the machine in cooperation with said cutter chain. It should also be noted that the main frame H is so arranged that the portion adjacent the advance side of the machine rests directly on the mine bottom and serves as a support for the machine while the portion adjacent the cuttings passageway is raised to form a bottomless passageway for the discharge of the cuttings. This prevents clogging of the cuttings between the bottom and top portions of the cuttings passageway in that the cuttings not expelled from the cuttings passageway by the cutter chain E4 are left behind as the mining machine travels along the working face.

Referring now in particular to the motor I8 and motor casing i8, and one of the novel features of my invention, it may be seen with reference to Figure 1 that the motor casing I8 is split diagonally of its length into two halves, herein referred to as a forward half 20 and a rearward half 2|. The forward half 20 is bolted to the rearward end of the main frame II by means of the nuts and bolts I9, and the two halves are detachably secured together by means of suitable nuts and bolts in a usual manner. The motor H] is provided with an armature 23 supported on a vertically extending armature shaft 24, and field coils 25, two of which field coils are supported in each half of the casing 38.

With reference to Figures 1 and 3, it may be seen that the motor is so arranged that it is slidable directly on the mine bottom adjacent an end Which is adjacent one end of the armature shaft 24. It may also be seen that the armature shaft 24 is supported in suitable bearings which in turn are supported in bearing supports 26 and 2? adjacent its upper and lower ends, respectively. The bearing supports 26 and 2? have a grooved outer periphery which is adapted to i be engaged by suitable tongues formed in the forward and rearward halves of the motor casing so the armature 23 may be removed therefrom with no vertical movement thereof. It should be noted that due to the fact that the motor casing is split diagonally, that its rearward half 2! may be removed from the forward half 29 with a minimum amount of rearward movement ith respect to the machine. With such an arrangement the armature 23 may be removed from the motor I!) when a breakdown occurs while the cutter bar is sumped under the coal. Thus the motor I8 is arranged so it may be readily accessible in confined spaces and all parts of the motor may be removed therefrom when the machine is at the working face under varying conditions of mining; as, for instance, where the space is very limited as to length and height but where there is ample width, which conditions are common in mines, especially where the roof is poor and it is necessary to space props for supporting the roof close to the working face of the coal.

Referring now in particular to the drive for the feed operating and cutter chain driving mechanism, and several other novel features of my invention, the upper end of the armature shaft 24 has an armature pinion 29 keyed thereto. The armature pinion Z9 meshes with and drives an idler gear 3!! journaled on its hub in suitable ball bearings supported in a bearing support 3!. The idler gear 30 is held in the bearing support 3! by means of astud 32 integral therewith having a nut threaded on its upper end, and meshes with and drives a spur gear 33 keyed on the upper end of the vertical shaft I6. Said spur gear is journaled on its hub in the bearing support 3| by means of suitable ball bearings of an ordinary construction. The bearing support 3| extends longitudinally of the main frame II and rearwardly therefrom and its rearward portion rests on the top end of the motor l0. Said bearing support is secured to said main frame by means of suitable cap screws in an ordinary manner, as may be seen with reference to Figure 3. The bearing support 3! is so arranged that it supports the idler gear 30 and spur gear 33 so said gears may readily be removed for accessibility to parts within the main frame H for removing the idler gear 33 from said bearing support and removing said bearing support from the main frame II.

A worm 34 is cut integral with the vertical shaft I6 and meshes with and drives a worm gear 35 keyed on a sleeve 36 freely mounted on a transversely extending shaft 31 for driving feed operating mechanism for the mining machine in a manner which will hereinafter be more fully described.

The cutter chain sprocket I5 is journaled on its hub in the main frame I I in suitable ball bearings and is provided with a plurality of upwardly extending clutch jaws 38 adapted to be engaged by clutch jaws 39 depending from a clutch member 40 feathered on the vertical shaft I 6 for selectively connecting said sprocket with said shaft for driving the cutter chain l4 therefrom.

The clutch member moved along the vertical shaft [6 by means of a suitable system of levers which may be of any construction, but which are herein preferably shown as comprising a clutch yoke 4i having engagement with said clutch member. The clutch yoke 4! is engaged by a clutch fork '42 keyed on a transversely extending rock shaft 43 supported in the main frame H forwardly of the vertical shaft [5 in suitable bearing supports in a usual manner. One end of the transversely extending rock shaft 43 extends beyond the lateral boundaries of the main frame H adjacent the advance side thereof and has a hand lever 44 keyed thereto so movement of said hand lever will vertically move the clutch member 48 to engage the clutch jaws 39 with the clutch jaws 35 or disengage said clutch jaws in an obvious manner. Suitable locking means are provided to lock the clutch jaws 39 in an engaged position with or disengaged position from the clutch jaws 3B, which means comprises suitable pin and aperture locking means generally indicated by reference character 45.

Referring now in particular to the feeding mechanism and method of operating the same, a feed drum 4? is provided. The feed drum 4'! is mounted on a stud 48 for free rotation with respect thereto and has an internal gear 49 keyed to its inner side, which internal gear meshes with and is driven by a spur pinion 5i! keyed on the forward end of the transversely extending shaft 31. The transversely extending shaft 3'! in turn is driven from the motor It by means of the worm gear 35, sleeve 36, and a frictionally controlled eccentric reduction device generally indicated at 5!, at either a high speed or a lower frictionally controlled speed in a manner which will hereinafter be more fully explained. Said feed drum may thus be rotated at a high speed or a variable low speed controlled by suitable friction means for winding 'a feed rope 52 thereon and moving the machine along the mine bottom by means of said rope at either a high positioning speed or a plurality of low cutting speeds.

Referring now in particular. to the details of the eccentric reduction device 5!, a casing 53 is journaled within the main frame H and rotatably mounted on the sleeve 36. An internal gear 54 is formed integral with a cage 55 and is journaled within the casing 53 for free rotation with respect thereto. An eccentric gear 56 meshes with the internal gear 54. The eccentric gear 56 has a lesser number of teeth than the internal gear 54 depending upon the reduction desired and is provided with a' plurality of lugs 51, .51 integral therewith and extending outwardly from one of its sides. The lugs 51, 51 have blocks 58,58 pivotally mounted thereon. The blocks 53 are slidable in guides 59 formed in the casing 53 and. disposed perpendicularly with respect to the axis of the transversely eX- tending shaft 31. r

It should be noted that the guides 59 are wider than the blocks 58 to permit lateral, as well as longitudinal, movement of said blocks within said guides,.the difference in width being dependent upon the difference in teeth between the internal gear 54 and eccentric gear 55.

The eccentric gear 55 is in turnrmounted on asuitable bearing 59, herein shown as being a ball bearing of an ordinary construction, which bearing 59 is mounted on an eccentric 5! formed integral with the sleeve 35.

Clutch jaws 63 are provided on the sleeve 36. Likewise, clutch jaws 54 are formed integral with the cage 55. A clutch member 55 is feathered on the transversely extending shaft 37 and extends within the casing 53 and is provided with clutch jaws 55 which may mesh with either the clutch jaws 55 or the clutch jaws 64.

Means are provided for retarding rotation of j the casing 53 or for allowing said casing to freely rotate with respect to the transversely extending shaft 31, which means herein comprise a friction band 57 engageable with the outer periphery of said casing; A forked member58 is secured to one end of the friction band 67. The ends of the forked member 68 are engageable with a projection 59 from the main frame ll. A lug i0 is attached to the opposite end of the friction'band 5?. A rod H extends through the lug l0 and has lock nuts 12 threaded to its lower end abutting the lower end of said lug. The rod H extends upwardly from the lug "H3 through the forked member 98 and projection 69 and has an eye-piece formed on its upper end which has a lever arm '53 pivotally connected thereto. The lever arm '13 is keyed on a transversely extending rock shaft 14-, which rock shaft is operated by means of a hand wheel 15 disposed adjacent the rearward end of the machine, and a suitable system of links and levers indicated at 16 in an obvious manner so rotationof said hand wheel in one direction will tighten the friction band 61 against the casing 53 and hold said casing from movement, while rotation of said hand wheel in an opposite direction will permit said casing to rotate with respect to said friction band.

When the eccentric 6! is driven from the motor l!)v and the casing 53 is held from rotation by the friction band 5.! the eccentric gear 55 will move in an orbital path towards and away from the shaft 31, which path is controlled by the guides 59 and blocks 58 slidable therein.

During orbital movement of the eccentric'gear 55, a certain number'of teeth thereof are continually in mesh with the teeth in the internal gear 54 and each timesaid eccentric gear'completely travels around its orbit, the internal gear 54 is moved a distanceequal to the widthof the number of teeth fully engaged therewith. The speed of rotation of the internal gear 54 is varied by varying the pressure of the friction band 5'! on the casing 53,- said friction band also acting as a safety device to prevent breakage of the feed operating mechanism upon overload of the feed drum -41.

' The clutch member 65 is shifted along the shaft ,3! to engage theclutch jaws 66 with either the clutch jaws 93 or the clutch jaws 64 by means squared upper end and is adapted to be engaged by a hand lever 82 so movement of said hand lever in one direction or another will move the clutch member 65 in one direction or another. Suitable pin and aperture locking means, indi cated at 83, are provided on the hand lever 82 for locking the clutch jaws 65 in a neutral position or in engagement with either the clutch jaws 63 or clutch jaws 64.

' Thus a means has been provided for driving the feed drum 4'5 at either a high speed orat lower variable speeds controlled by the friction band 61, which means is of a simplified construction and is so arranged as to safely take care of overloads on said feed drum and prevent breakage of the feed operating parts and takeup a minimum amount of space in the machine.

Suitable means are provided to retard the rearward end of the mining machine as it is being fed across the coal face by the feed rope 52 and feed drum 4! which may be of any construction, but which herein comprises a retarding drum 84 having a cable 35 wound thereon. The retarding drum 8-?3 is freely mounted on a stud 85 extending rearwardly'from the rearward end of the rearward half 2| of the motor casing l8 Means are provided to retard the rotation of the retarding drum 84 and control the paying off of the cable 85 therefrom, which means, as herein shown, comprises a brake band 8'! engageable with said drum and operated by means of a suitable hand wheel83 in an obvious manner.

The feed rope 52 may be trained around a sheave 89 adjacent the forward advance side of the machine for feeding said machine across the face during the normal cutting operation, or; said feed rope maybe trained rearwardly from the feed drum ii around a sheave 90 disposed adjacent the rearward advance side of the motor Q casing is and around a sheave 9i disposed adjacent the central portion of the motor casing i8 for pulling the mining machine upon the truck if in a usual manner, which may be clearly understood with reference to Figure 1. Likewise, a sheave 92 is provided adjacent the rearward retreating side of the machine so the feed rope 52 may be trained therearound for sumping the cutter bar [2 into the coal, or for pulling said machine in a direction opposite to its normal direction oftravel. 7

Referring now in particular to the means for driving the truck I! about the mine, a spur gear 93 'is keyed on the hub of the spur gear 33 and meshes with and drives a spur gear 94 on one end .98 is provided with a squared socket in its outer end which is engageable with a squared coupling pin 99 mounted in the hub of a drive sprocket I00 for slidable movement with respect'thereto. The drive sprocket I90 is journaled'on its :hub in a bearing support IIII extending upwardly from the track mounted truck I'I. Means are provided for holding the coupling pin 99 in engagement with the squared socket in the transversely extending shaft 98, which means herein comprise a locking member I62 pivotally connected at one of its ends to an arm integral with the bearing support II and extending outwardly therefrom around one side of the drive sprocket I00 and having locking engagement with another arm extending outwardly from the bearing support IOI around the opposite side of said drive sprocket. The drive sprocket I00 is connected with forward truck wheels 103 for driving said truck wheels by means of a chain and sprocket drive indicated at I04. The forward and rearward truck wheels are in turn operatively connected together by means of a suitable chain and sprocket drive I05.

It may thus be seen that when the mining machine has been pulled on the truck II by means of the feed rope :52 that the coupling pin 89 may be engaged with the squared socket in the transversely extending shaft '98 for driving the truck I! and moving the mining machine about the mine from working place to working place.

While I have herein shown and described one embodiment of my invention, it will be understood that the construction and arrangement of the various parts may be altered or changed without departing from the spirit or scope thereof. Furthermore, I do not wish to be construed as limiting myself to the specific form illustrated, excepting as it may be limited in the appended claims.

I claim as my invention:

1. In a mining machine, a frame, feedingmeclr anism therefor comprising a feed drum disposed on one side of said frame for rotation about an axis disposed transversely thereof, cutting mechanism extending forwardly of said frame including a chain carrying cutter bar, and meansfor driving said feeding and cutting mechanism comprising a motor having an armature shaft rotatable about a vertical axis, said motor including-a motor casing slidable directly on the mine bottom and having detachable connection with the rearward end of said frame, said motor casing being split in a vertical plane extending diagonally of said frame and separable to one side of said frame.

2. In a mining machine, a motor having a vertically disposed armature shaft, a casing for said motor engageable directly with the mine bottom, said casing being split diagonally in a vertical plane and the size thereof substantially deter-- mining the power producing function of said motor, a frame disposed forwardly of said motor having a projecting cutter bar extending forwardly therefrom, said cutter bar being disposed in planes which intersect said motor, feed operating and controlling means on said mining machine comprising a feed drum disposed adjacent the advance side of said mining machine forwardly of said motor for rotation about a transverse axis, and means for driving said feed'drum from said motor at either a high speed or a low frictionally controlled speed comprising a vertical shaft driven by said motor, .a worm gear driven therefrom and disposed rearwardly of said vertical shaft, a frictionally controlled gear reduction device interposed between said worm gear and, said feed drum, a shaft coaxial with said frictionally controlled gear reduction means and driven therefrom, and 1a geared reduction between said shaft .and said feed drum.

3. In ,a mining machinea frame, .a motor having ,an armature shaft rotatable about a vertical axis, said motor being slidable directly on the mine bottom and'being connectible with the rearward end .of said frame, cutting mechanism therefor including a projecting cutter bar extending forwardly of saidframeand having a cutter chain movable therea-b'out, feeding mechanism therefor comprising a feed drum having aflexible feeding member adapted to be wound thereon, said feed drum being disposed adjacent the advance side of said frame for rotation about a horizontal axis, andmeans for selectively driving said feeding and cutting mechanism from said motor comprising a vertically disposed shaft driven from said armature shaft having a cutter chain sprocket .freely mounted on its lower end, .clutchmeans for connecting said sprocket with said shaft, .a transverse shaft spaced closer to said motor than said verticalshaft, a worm gear coaxial with said shaft and driven by said verticalshaft, a frictionally controlled gear reduction device coaxial therewith, clutch means for operatively connecting said transverse shaft with said frictionally con trolled gear reduction device, and a geared connection from said shaft to said'feed drum.

4. In aimining machine, .a frame, a cutter bar having a cutter chain movable thereabout projecting forwardly of said frame, feed operating means on said frame comprising a'feed drum disposed adjacent the advance side of said frame when said mining machine is cutting alonga coal face, drive .means for said feed drum comprising a vertical shaft, a transversely extending shaft disposed rearwardly of said vertical shaft and driven therefrom, a geared connection from said shaft to said feed drum, and a motor disposed rearwardly of said transversely disposed shaft having a vertical armature shaft operatively connected with said aforementioned vertical shaft, said motor including a motor casing slidable directly on .the mine bottomand split in a vertical plane extending diagonally of said frame and separable to one side of said frame.

5. Ina mining machine, a frame, a motor having a vertical armature shaft, feeding mechanism therefor comprising a feed drum disposed on one side of :said frame for rotation about an axis extending transversely thereof, cutting mechanism projecting forwardly of said frame including a chain carrying cutter bar, means for driving said feeding and cutting mechanism from said motor comprising a vertical shaft spaced forwardly of said armature shaft, a plurality of reduction gears driven from said armature shaft and having driving relation with :said vertical shaft, and support means for said gears comprising a bearing member detachably secured to the upper portion of said frame andforming a detachable'bearingsupport forsaid gears.

6. Ina mining machine, aframe, amotor having a vertical armaturashaft, feeding mechanism therefor 'comprisinga feed drum disposed on one side of said frame for rotation about an axis extending transversely thereof, cutting mechanism projecting forwardly of said frame including a chain carrying cutter bar, means for driving said feeding and cutting mechanism from said motor comprising a vertical shaft spaced forwardly of said armature shaft, a plurality of vreductiongears driven from said armature shaft and having driving relation with said vertical shaft, and support means for said gears comprising a bearing memher having a portion extending rearwardly of said frame adapted to rest on the upper end of the easing for said motor, said bearing member being detachably secured to the upper portion of said frame and forming a detachable support for said gears.

7. In a mining machine, a frame, a motor having a vertical armature shaft, feeding mechanism therefor comprising a feed drum disposed on one side of said frame for rotation about an axis extending transversely thereof, cutting mechanism projecting forwardly of said frame including a chain carrying cutter bar, means for driving said feeding and cutting mechanism from said motor comprising a vertical shaft spaced forwardly of said armature shaft, a plurality of reduction gears driven from said armature shaft and having driving relation with said vertical shaft, and support means for said gears comprising a bearing member extending longitudinally of said frame and having a portion extending rearwardly of said frame adapted to rest on the upper end of the casing of said motor, said bearing member being detachably secured to said frame adjacent the forward and rearward ends thereof and forming a detachable support for said gears.

CHARLES A. PRATT. 15 

